The most potent risk factor for the development of bipolar disorder (BP) is a first-degree family member with the illness. Thus, offspring of parents with BP are a particularly high-risk group and typically experience early illness onset, severe course, and high rates of comorbid psychiatric disorders. It is well-established that poor sleep regulation is associated with the onset of depressive and manic episodes among individuals with a biological vulnerability to mood disorder. Furthermore, evidence supports sleep disturbance in at-risk youth who have not yet developed threshold mood disorders. The proposed study aims to address this core disturbance that we argue puts at-risk youth at even greater risk for development of BP-sleep and social rhythm disruption. Since adolescence is a period characterized by significant alterations in sleep/wake patterns and social routines, this period may prove optimal for assessment and treatment of sleep and psychiatric symptoms in those at-risk. We adapted and piloted Interpersonal and Social Rhythm Therapy (IPSRT), an empirically-supported treatment for adults with BP that helps patients stabilize sleep/wake cycles and daily routines, for at-risk adolescents. Preliminary data indicate this approach holds promise as for youth at-risk for the development of BP. We also identified intervention for the heterogeneous conditions antecedent to BP as a second path to preventing or delaying BP onset in at-risk youth. The purpose of the proposed study is thus to further develop and examine IPSRT for the adolescent (age 12-18) offspring of parents with BP. The study involves conduct of a small controlled trial (n=50) comparing Brief IPSRT + Data-Informed Referral versus Data-Informed Referral alone to gather preliminary data on feasibility, acceptability and proximal outcomes associated with the intervention. All participants receive a thorough assessment of psychopathology and sleep disturbance (via objective and subjective methods) at baseline, followed by a single feedback session reviewing the findings. As clinically indicated, youth will be offered Data-Informed Referral for any psychiatric symptoms/disorders identified during the intake assessment. Youth will then be randomized to receive either Brief IPSRT or no Brief IPSRT; randomization will be stratified on sleep disturbance and psychopathology. Outcomes will be assessed at 4 time points over 6 months in all participants. Data will be used to inform the design and conduct of a future controlled trial. The proposed approach is in direct accord with strategies outlined in the NIMH Strategic Plan in which the development and testing of innovative interventions to reduce risk and positively alter trajectories of mental illness are informed by research findings regarding robust and malleable risk factors and core features of disease. Research in this area is of great public health importance, as it has the potential to prevent, delay, or ameliorate the progression of this chronic and devastating illness in those at highest risk.